1. Field of the Invention
The present invention relates generally to a flush valve and, more particularly, to a valve that allows an internal combustion engine cooling system to be flushed by providing an external source of fresh water and connecting the external water source to the valve which is connected in fluid communication with the cooling system of the internal combustion engine.
2. Description of the Prior Art
In certain applications, it is necessary to periodically flush the cooling system of an internal combustion engine. In particular, when an internal combustion engine is used as a power source or a marine propulsion system, such as a stern drive, inboard system, or outboard motor, the marine propulsion system typically uses cooling water taken from the body of water in which the marine propulsion system is used. If the body of water contains salt water and is caused to flow within the cooling passages of the engine, a residue can be deposited on the internal surfaces of the engine. This sea water residue can eventually clog certain passages. In addition, the sea water residue can provide a corrosive atmosphere which can severely damage certain metals. It is therefore advisable to periodically flush the cooling system of the engine with fresh water in order to clean the surfaces of the cooling system and remove the sea water residue and debris. Many different techniques have been developed for flushing the cooling system of marine engines used in salt water applications.
U.S. Pat. No. 5,671,906, which issued to Rosen on Sep. 30, 1997, discloses a flush valve for a water cooled marine outboard engine having a flush orifice. The flush valve includes a valve body with an engine attachment end and a flush water source end. The valve body has a channel between the engine end and the source end. The engine end of the valve body can be affixed into the flush orifice of the engine. The flush valve also includes a means for obstructing a discharge flow of cooling liquid from the engine end of the hollow valve body.
U.S. Pat. No. 5,123,369, which issued to Gross on Jun. 23, 1992, discloses a marine valve structure. The valve apparatus is intended for use with a marine vessel. It has a housing with first, second, and third ports and a valve member within the housing. The housing is mounted to the hull of the vessel with the first port communicating with the body of water outside the vessel. The third port is connected to the cooling system of an engine in the vessel and the second is closed by a quick release plug. The valve member is moveable to open and close communication with the outside. During normal operation, water is drawn through the structure into the engine cooling system and is discharged overboard. In an emergency, the plug can be removed and the valve member moved to a 90.degree. position in which the communication with the outside is closed, allowing the engine to draw water from within the hull and discharge it overboard. The structure can also be used with a service adapter for engine flushing and other maintenance.
U.S. Pat. No. 5,251,670, which issued to Bates on Oct. 12, 1993, discloses a flush valve. The valve is used for alternately supplying fresh water or sea water coolant to marine engines. Such valve, used in combination with marine engine cooling systems, facilitate the flushing of contaminants. In one embodiment the valve includes a first portion having inlet conduits, a second portion having outlet conduits, and a means for rotatably securing the first and second portions together with minimum gap therebetween. Inlet and outlet portions are alternately positioned in a first, single fluid flow relationship (sea water supply) wherein only a first fluid is directed through outlet conduits, or in a second, multiple fluid flow relationship (flushing operation) wherein both a first and a second fluid are sent to outlet conduits. Also, sealing means is provided between the first and second portions to prevent liquid from escaping through the gap therebetween. In another embodiment, the inlet and outlet portions are stationary and a coupling means situated between the portions is alternately positioned to switch the fluid flow relationship. In yet another embodiment, a coupling means is alternately positioned in a first, dual fluid flow relationship, or in a second, dual fluid flow relationship wherein the fluid delivered to the outlet conduits is reversed. The valves may also be useful in industrial applications.
U.S. Pat. No. 5,010,836, which issued to Riviezzo, on Apr. 20, 1991, describes a live well valve for fishing boats. A leak-tight rotatable plug valve for controlling water flow to and from a fish live well in a fishing boat is described in which the valve body has opposite ends connected with an inlet hose for fresh water intake and a drain hose extending from the live well drain. A pump inlet passage in the valve body intersects the valve flow passage and mounts a pump having its discharge connected with a supply hose leading to the live well. When the valve is open, fresh water can be pumped to fill the live well w hen the pump is active and the live well can be drained when the pump is inactive. When the valve is closed, the pump recirculates water through the drain hose and supply hose to avoid stagnation and provide aeration for the live well.
U.S. Pat. No. 4,004,533, which issued to Woolston, on Jan. 25, 1977, discloses a scuttling valve. The valve assembly permits the automatic scuttling, or sinking, of floatable pressure vessels or other containers and comprises an extensible, spring restrained nozzle containing a spring biased ball seal within a flow passage. Vessel internal pressure extends the nozzle from a retracted position to expose the exterior end of the flow passage. A calibrated restraining spring ring maintains the nozzle retracted and in the extended position during pressure vessel operation. The ball seal is displaced from a nonsealing position against a ball seat to preclude pressure relief through the flow passage. After exhaustion of internal pressure, the bias spring and external water pressure force the ball seal from the ball seat to permit water entry and subsequent sinking of the vessel.
U.S. Pat. No. 4,341,224, which issued to Stevens, on Jul. 27, 1982, discloses a catheter flushing apparatus. The flow control apparatus has a flow passage with an inlet and outlet. It is provided in a housing. A control means having a conical valve seat and ball member for restricting flow through the seat is provided in the inlet of the passage. A valve plunger is slidably located within the housing and is resilently biased against a second valve seat provided in the passage walls of the housing. The plunger includes a marine bore capillary passage which effectively bypasses the second valve seat, thus permitting a first flow. When the plunger is moved from its seat, a second higher flow is established for flushing the device. This second higher flow rate is controlled by valve control means in the inlet of the passage in order to prevent excessively high flow rates.
U.S. Pat. No. 5,393,252, which issued to Brogdon on Feb. 28, 1995, discloses a fresh water flushing system for a marine engine system in a boat. It can be used whether the boat is in or out of the water. The system comprises a control panel mounted in the proximity of the marine engine and a fresh water flush valve. Hoses are connected to the fresh water flush valve and to various components of the marine engine system in order to provide fresh water fluid flow within the engine. Alternative embodiments of the system are described in marine vessels with more than one engine.
U.S. Pat. No. 5,362,266, which issued to Brogdon on Nov. 8, 1994, describes a fresh water flushing system for a marine engine. The system comprises a control panel that is mounted on the interior of the boat, a plurality of tubular "T" shaped interconnection fittings in a raw sea water cooling circuit, and a fresh water flush valve therebetween. The components are connected for fresh water fluid flow with a plurality of standard radiator hoses. The fresh water flush valve has a valve plunger for establishing fresh water flow between the control panel and the "T" shaped interconnection fittings. Furthermore, the fresh water flush valve has a plurality of axial outlet ports to proportionately direct the flow of fresh water to the appropriate interconnection fitting in the raw sea water cooling conduit of the marine engine. A valve plug is provided to secure a positive closure when the fresh water flow is disconnected. The valve plug has a tapered body and an O-ring to effect a positive seal and ensure that no fluid backflow occurs when the flushing system is not in use and the marine engine is operating under normal conditions in sea water. All of the fixed and moveable parts are fabricated from material that resists salt air and salt water corrosion.
U.S. Pat. No. 4,359,063, which issued to Carlson on Nov. 16, 1982, discloses a spring-biased flushing accessory for outboard motors. The self-gripping spring-biased accessory directs water from an outside source in order to flush the cooling system of a marine engine. The accessory comprises a U-shaped retainer which terminates at its ends in a pair of resilient suction cups which are constructed to bear against the cooling water intake ports on opposite walls of the engine housing. At least one of the cups is connected to an external source of flushing water. A particular feature of the invention, which is disclosed in several different embodiments, is that the U-shaped retainer is provided with an auxiliary device to impart a spring-bias to the legs and urge them to move towards one another to secure the suction cups in resilient sealed relation against the cooling water intake ports. In one modification of the invention, a device is provided to apply the flushing water simultaneously to intake ports on opposite sides of the engine housing.
U.S. Pat. No. 4,065,325, which issued to Maloney on Dec. 27, 1977, describes an adaptable flush attachment for marine engines having side cooling ports. The device is a universally adaptable component for use in flushing outboard and inboard/outboard marine engines. This is made possible by the unique design of the strap and the shape of the cups which allow for the device to attach against the motor shaft housing on motors having shaft housings of different dimensions and contours.
U.S. Pat. No. 4,540,009, which issued to Karls on Sep. 10, 1985, discloses a flushing device for an outboard motor. The device supplies water to the cooling water inlets of an outboard motor and uses a connecting pin extending through the inlets to attach a pair of sealing cups over the inlets. A sliding spring latch releasably attaches one of the cups to the connecting pin. A hose connection allows water to be supplied to the inlets through the cups.
U.S. Pat. No. 4,589,851, which issued to Karls on May 20, 1986, describes a flushing device for an outboard motor. The device is provided so that water can be supplied to an inlet which is provided on the bottom of the anti-ventilation plate of an outboard motor. The flushing device uses a mounting bracket to hold a resilient cup compressed in place over the water inlet. A hose connector allows the cup to be connected to a water supply.
It would be beneficial if a flush valve could be provided that allowed a boat operator to simply connect a fresh water source (e.g. a hose) to the valve without having to manipulate the valve in any way prior to flushing the cooling system of the engine with fresh water. It would also be beneficial if a flush valve of this type could be made in such a way that it was not easily clogged with sand or other debris. In addition, it would be beneficial if a flush valve of this type could be manufactured in a way that avoiding the possibility that a valve failure could block the normal flow of cooling water to the engine. Regardless of the precise cause of such a failure, it is necessary to avoid the possibility that a failure of the valve could adversely affect the normal cooling water path for the engine. In other words, a valve of this type should operate in a fail safe manner. It would also be beneficial if a flush valve of the type described above could be manufactured at a relatively low cost and consist of few moveable components. It would also be beneficial to assure that a slight flow of fluid was available to a sea pump impeller in the event that the operator chooses to operate the engine during the flushing procedure.